fix sleeping UE when PSS detection is wrapping over frame buffer

openair1/PHY/NR_UE_TRANSPORT/nr_initial_sync.c

@@ -48,8 +48,6 @@
 
 //static  nfapi_nr_config_request_t config_t;
 //static  nfapi_nr_config_request_t* config =&config_t;
-int cnt=0;
-
 // #define DEBUG_INITIAL_SYNCH
 #define DUMP_PBCH_CH_ESTIMATES 0
 
@@ -137,12 +135,9 @@ static bool nr_pbch_detection(const UE_nr_rxtx_proc_t *proc,
 nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, int n_frames, int sa)
 {
   int32_t sync_pos, sync_pos_frame; // k_ssb, N_ssb_crb, sync_pos2,
-  int32_t metric_tdd_ncp = 0;
-  uint8_t phase_tdd_ncp;
-  int frame_id;
 
   NR_DL_FRAME_PARMS *fp = &ue->frame_parms;
-  nr_initial_sync_t ret = {true, 0};
+  nr_initial_sync_t ret = {.cell_detected = false};
 
   VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_NR_INITIAL_UE_SYNC, VCD_FUNCTION_IN);
 
@@ -163,13 +158,10 @@ nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, i
 
   const uint32_t rxdataF_sz = ue->frame_parms.samples_per_slot_wCP;
   __attribute__((aligned(32))) c16_t rxdataF[ue->frame_parms.nb_antennas_rx][rxdataF_sz];
-  cnt++;
-  if (1) { // (cnt>100)
-    cnt = 0;
 
   // initial sync performed on two successive frames, if pbch passes on first frame, no need to process second frame
   // only one frame is used for symulation tools
-    for (frame_id = 0; frame_id < n_frames; frame_id++) {
+  for (int frame_id = 0; frame_id < n_frames && !ret.cell_detected; frame_id++) {
     /* process pss search on received buffer */
     sync_pos = pss_synchro_nr(ue, frame_id, NO_RATE_CHANGE);
     if (sync_pos < fp->nb_prefix_samples)
@@ -181,9 +173,12 @@ nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, i
     LOG_I(PHY, "[UE%d] Initial sync : Estimated PSS position %d, Nid2 %d\n", ue->Mod_id, sync_pos, ue->common_vars.nid2);
     LOG_I(PHY, "sync_pos %d ssb_offset %d \n", sync_pos, ue->ssb_offset);
 #endif
-
     /* check that SSS/PBCH block is continuous inside the received buffer */
-      if (ue->ssb_offset + NR_N_SYMBOLS_SSB * (fp->ofdm_symbol_size + fp->nb_prefix_samples) < fp->samples_per_frame) {
+    if (ue->ssb_offset + NR_N_SYMBOLS_SSB * (fp->ofdm_symbol_size + fp->nb_prefix_samples) >= fp->samples_per_frame) {
+      LOG_I(PHY, "Can't try to decode SSS from PSS position, will retry (PSS circular buffer wrapping): sync_pos %d\n", sync_pos);
+      continue;
+    }
+
     // digital compensation of FFO for SSB symbols
     if (ue->UE_fo_compensation) {
       double s_time = 1 / (1.0e3 * fp->samples_per_subframe); // sampling time
@@ -219,10 +214,12 @@ nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, i
 #endif
 
     int freq_offset_sss = 0;
-        bool ret_sss = rx_sss_nr(ue, proc, &metric_tdd_ncp, &phase_tdd_ncp, &freq_offset_sss, rxdataF);
-        ret.cell_detected = ret_sss; // rx_sss_nr returns true if success
+    int32_t metric_tdd_ncp = 0;
+    uint8_t phase_tdd_ncp;
+    ret.cell_detected = rx_sss_nr(ue, proc, &metric_tdd_ncp, &phase_tdd_ncp, &freq_offset_sss, rxdataF);
+    
     // digital compensation of FFO for SSB symbols
-        if (ue->UE_fo_compensation) {
+    if (freq_offset_sss && ue->UE_fo_compensation) {
       double s_time = 1 / (1.0e3 * fp->samples_per_subframe); // sampling time
       double off_angle = -2 * M_PI * s_time * freq_offset_sss; // offset rotation angle compensation per sample
 
@@ -236,7 +233,6 @@ nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, i
           ue->common_vars.rxdata[ar][n].i = (short)(round(re * sin(n * off_angle) + im * cos(n * off_angle)));
         }
       }
-
       ue->common_vars.freq_offset += freq_offset_sss;
     }
 
@@ -284,21 +280,6 @@ nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, i
         ret.rx_offset = ue->ssb_offset - sync_pos_frame;
     }
 
-        /*
-          int nb_prefix_samples0 = fp->nb_prefix_samples0;
-          fp->nb_prefix_samples0 = fp->nb_prefix_samples;
-
-          nr_slot_fep(ue, proc, 0, 0, ue->ssb_offset, 0, NR_PDCCH_EST);
-          nr_slot_fep(ue, proc, 1, 0, ue->ssb_offset, 0, NR_PDCCH_EST);
-          fp->nb_prefix_samples0 = nb_prefix_samples0;
-
-          LOG_I(PHY,"[UE  %d] AUTOTEST Cell Sync : frame = %d, rx_offset %d, freq_offset %d \n",
-          ue->Mod_id,
-          ue->proc.proc_rxtx[0].frame_rx,
-          ue->rx_offset,
-          ue->common_vars.freq_offset );
-        */
-
 #ifdef DEBUG_INITIAL_SYNCH
     LOG_I(PHY,
           "TDD Normal prefix: CellId %d metric %d, phase %d, pbch detected %d, measured offset %d\n",
@@ -308,17 +289,6 @@ nr_initial_sync_t nr_initial_sync(UE_nr_rxtx_proc_t *proc, PHY_VARS_NR_UE *ue, i
           ret.cell_detected,
           ret.rx_offset);
 #endif
-
-      } else {
-#ifdef DEBUG_INITIAL_SYNCH
-        LOG_I(PHY, "TDD Normal prefix: SSS error condition: sync_pos %d\n", sync_pos);
-#endif
-      }
-      if (ret.cell_detected)
-        break;
-    }
-  } else {
-    ret.cell_detected = false;
   }
 
   /* Consider this is a false detection if the offset is > 1000 Hz